This invention relates to shipping packages, in particular, packages, or "specimen mailers", for shipping biological and chemical specimens via the postal service.
In the medical and chemical arts it is frequently necessary to ship biological and chemical specimens from one point to another via the postal service, for example when a specimen is sent to a medical laboratory for testing and analysis. Typically, such specimens comprise fluid placed in glass test tubes and on glass slides which must be protected from shock during handling, due to the fragile nature of the test tubes and slides, in order to prevent breakage. At the same time, it is desirable to prevent the specimens from contaminating or damaging other mail, or other specimens, in the event that leakage occurs. Accordingly, such specimens are ordinarily placed in a protective, shock-resistant package, or "specimen mailer", typically made of polystyrene plastic foam, such as that sold by Dow Chemical Co. of Midland, Mich. under the trademark STYROFOAM, and designed to hold a plurality of such specimens.
One type of known specimen mailer, for example that disclosed in U.S. Pat. No. 3,446,342, utilizes an elongate block of polystyrene plastic foam in the form of a rectangular prism with a row of in-line apertures formed therein for receiving specimen containers. The containers, which typically comprise as many as eight elongate test tubes with caps and at least one elongate box for holding specimen slides, are enclosed by the block except for their capped ends and are held within the block by friction force produced as a result of making the apertures slightly undersized for the specimen containers. In addition, ridges are ordinarily formed in the plastic foam along two sides of the row of protruding containers to protect the protruding ends from damage, and once the containers are inserted the block is placed within a paper envelope for protection and to provide a place for mailing instructions and postage.
Another type of known specimen mailer, for example a Model 341 specimen mailer sold by Polyfoam Packers Corp. of Chicago, Illinois, comprises a thin rectangular prismatic block of plastic foam formed from two interlocking symmetrical parts which divide the block in half along its thin dimensions. Inside the block, each part contains a row of in-line recesses for receiving and partially enclosing specimen test tubes and slides, which are fully enclosed by both parts of the block when the two parts are placed together. Such a container is also typically placed in a paper mailing envelope.
While the afore-described types of prior art specimen mailers provide some protection for specimen containers shipped therein, there is a need for an improved specimen mailer which makes more efficient use of space to reduce its size and weight, thereby reducing manufacturing and mailing costs, which better facilitates insertion and removal of specimen containers, and which prevents contamination of other mail and specimens from specimen-container leakage. In addition, it would be desirable for such a mailer to provide greater protection against shock to the specimen and be readily adaptable for reuse.